Operating rod latching mechanism for firearms



arch 7, l950 J. c. GARAND 2,499,378

OPERATING ROD LATCHING MECHANISM FR FIREARMS Filed April 10, 1946 v ze :E :l: E l .855 4ZM737' /9`3 /7 ghwu; 2

lIlIllllllllllllIlIIlllllllllllllllllllllllmmm """l'lrrul ,Jill-1n E. E111-rund 7 4 @Ww-MMM" W l Patented Mar. 7, 1950 OPERATING ROD LATCHIN G MECHANISM FOR FIREARMS John C. Gai-and, Springfield, Mass. Application April 10, 1946, Serial No. 661,049

(Cl. l12---16) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 6 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to an improvement in automatic firearms of the reciprocating bolt type and more particularly to a latching device for securing the bolt mechanism in a retracted position.

There are various reasons for the desirability of latching the bolt mechanism of an automatic firearm in a retracted position at the will of the operator. Among such reasons is the recurring necessity for ready access to the barrel chamber for cleaning purposes or for determining whether the firearm is loaded. Another is the advantage of more rapid cooling of the barrel and chamber after a prolonged burst of automatic ring.

Accordingly it is an object of this invention to provide superior manual means whereby the bolt mechanism of an automatic rearm may be secured in a retracted and open position.

Furthermore, in a firearm of the type commonly known as the U. S. rie, cal. .30, Ml, the operating rod used to retract the bolt occasionally exhibits a tendency to jump out of the disassembly notch located in a longitudinal groove in the receiver.

Therefore a particular object of this invention is to provide means for preventing the operating rod of the U. S. rie, cal. .30, M1 from disengagement with the receiver thereof while such rod is reciprocating.

The specific nature of this invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a fragmentary side elevational view of a firearm showing the operating rod and bolt in battery position and the operating rod lock in an inoperative position;

Fig. 2 is a fragmentary side elevational View of the firearm with the operating rod and bolt secured in the recoil position by the operating rod lock;

Fig. 3 is a detail sectional view showing the manner of mounting the lock in the receiver taken along line 3-3 of Fig. 1; and

Fig. 4 is a perspective view of the operating rod lock member detached from the rearm.

The particular firearm chosen for purposes of illustrating the present invention includes in assembled relation a receiver I, a bolt 2, an operating rod 3, spring I8 and a stock 25. A rear sight provided with a windage knob 23 on the righthand side of such sight is shown mounted on receiver. Details of the construction and operation of these main elements are common to the U. S. rifle, cal. .30, M1. However, receiver I has been modified somewhat to accommodate the latch mechanism of the present invention.

This latch mechanism referred to hereafter as the operating rod lock 4 is contained within a horizontally disposed circular recess 9 extending transversely and nearly through the bridge 5 of receiver I. As shown in Fig. 4 the lock 4 consists of a cylindrical body portion 6 with a finger piece 'l integral therewith. Two adjacent angularly displaced transverse slots, indicated generally by 8 and having one end thereof arcuately formed as shown at I6 and I6' communicate with one another in such manner that the walls thereof are eliminated and thereby form two diametrically opposed camming projections I0. The angular relationship of slots 8 permits positioning of lock 4 with respect to a transverse pin I5 as will be later described. An axial circular recess I2 intersecting the angular slots 8 extends substantially three-quarters of the length of the lock body portion 6.

The linger piece I is a lever-like member perpendicularly disposed to the axis of body portion 6 and is provided with an inwardly projecting. arcuately formed arm 26 which has serrations I I on the outer surface thereof for preventing finger slippage. A lower depending portion of linger piece 1 ends in a projecting tip 2U the purpose of which will later be explained.

When the operating rod lock 4 is positioned within the receiver-bridge 5, the cylindrical body portion 6 of lock 4 rests against a spring I4 which exerts a force tending to effect longitudinal displacement of lock 4 in circular recess 9. Lock 4 however is retained there by transverse pin I5 as shown in Fig. 3.

With the operating rod lock 4 in the unlocked position as shown in Fig. 1, pin I 5 engages one set of the arcuate ends IE of the angular slot combination 8. Pin I5 is slightly tapered and when inserted into receiver bridge 5 from the rear thereof is held in place by a rear sight cover (not shown). Rearward rotation of nger piece 1 however causes the other and adjacent set of arcuate ends I6' to engage pin I5. Projections I0 formed by arcuate ends I6 and I6 provide a camming action by slidably moving against pin I5 thereby effecting longitudinal displacement of lock 4 against the bias of spring I4. When sufficient rotation thereof has been accomplished to cam projections I0 over pin I5, the bias of compressed spring I 4 returns lock 4 to its original depth in the circular recess 9 of the receiverbridge 5, but this time in the diametrically opposite set of arcuate ends I6. The sides of the angular slot combination 8 limit the extent of rotation of lock 4.

When operating rod 3 is retracted to the rear and operating rod lock 4 is rotated rearwardly,

the projecting tip 20 of finger piece 1 extends downwardly in front of a shoulder I'I of operatandere ing rod 3 land restrains such from returning to its forward position against the bias of operating rod spring I8. The operating rod 3 engages bolt 2 in a manner known to those familiar with the Ml rifle. Accordingly both of such members are, held rearwardly by the engagement Vof operating rod lock 4 with shoulder I 'i of operating rod `3 thereby providing easy access to the barrel chamber (not shown).

In the event the operating rod lock d is inadvertently left in the locked position shown in Fig. 2, the reciprocable operating rod 3 will cam lock 4 back to the non-operating-or unlocked position of Fig. 1. This is effected by a rear shoulder I9`of operating rod 3 striking the projecting tip 2i! of finger piece 'l thereby causing operating rod lock 4 to rotate .forwardly .as operating rod 3 is moved to therecoil position.

Alongitudinal groove 2| in thereceiver l along which the operating rod .3 rides when retracted rearwardly, contains va disassembly notch '22 positioned underneath the rear sight windage knob 23 to allow an upward movement of the rear end of the rod V3 thereby permitting removal of the rod outwardly. Operating rod 3 is provided with atop surface 21. The bottom surface I3 of finger piece l when in contact with surface 21 prevents operating rod 3 `from moving upwardly and out of engagement with `longitudinal groove v2| when retracted to lthe disassembly notch 22. When lock 4 is pressed into the circular recess 9 against the bias of spring ifi, surface i3 does not block surface 2 and operating rod 3 can then be moved upwardly allowing vdisassembly of such rod.

Thus there is here provided an improved :man- ,f

ual means for latching the bolt mechanism of an automatic firearm in a retracted position, to permit `cleaning or inspection of the bore thereof lor to maintain the breech mechanism in the openI position to facilitate cooling after prolonged ..1

bursts of firing.

I claim:

l. In a firearm having a receiver, a reciprocable bolt, and an operating rod connected `thereto, a lock rotatably mounted for securing the bolt in a recoil positioncompr-ising, a cylindrical 'body portion, said body `portion being provi-ded with two Vangularly displaced lateral slots having one end thereof arcuately formed, said angular slots communicating with one another in such manner that the wall therebetween is eliminated,` said body portion having a bore 4extending substantially therethrough whereby said bore produces two diametr'ically opposed camming projections by the intersection of said bore with said slots, a finger piece on said body portion having an ari-n for effecting rotation thereof, and a projection on said finger piece engaging the operating rod for securing the rod in a retracted position.

2. In a nrearrn having a receiver, a reciprocable bolt, and an operating rod connected thereto, a lock for securing the bolt Yin a recoil position comprising, a cylindrical body `portion having a finger piece, said body portion being provided with two angularly displaced lateral slots having one end thereof arcuately formed, said angular slots communicating with one another in such manner that the wall therebetween is eliminated, said body portion having a bore extending substantially therethrough whereby said bore produces two diametrically opposed camming projections by the intersection of said bore with said slots, said body portion adapted to be inserted for rotatable movement within a recess in the receiver, resilient means lexciting a bias said projections to re-engage said pin with the other rpair of oppositely disposed arcuate ends,

.said resilient means in combination with said pin yieldinglysecuring` said body portion in either of the two positions for holding the rod in a retracted' position or to permit release therefrom.

3. In a firearm having a receiver, a reciprocable bolt and an operating rod connected thereto, the operating rod provided with a forward cam surface, a vlock rotatably mounted *for securing the bolt in a recoil `position comprising, a cylindrical body portion, .a finger piece attached thereto, and a projection yon said finger piece, all adaptedand arranged to engage the cam surface lof the operating rod when said lock is rotated rearwardly thereby securing the operating rod ina retracted position.

4. In a firearm having a receiver, a reciprocable bolt and anv operating rod-connected thereto, the operating rodV provided with a rear cam surface, a lock rotatably mounted comprising a cylindrical body portion, a finger piece connected thereto, and a projection on said nger piece, all adapted and-arrangedV whereby, in the event said lock has been rotated rearwardly thereby pivoting said projectiony into the path of the operating rod, the cam surface thereof will strike said projection effecting the rotation of said lock to a non-operating position.

5. In la firearm having 4a receiver, `a reciprocable bolt andanoperating rodconnected thereto, the receiver being .provided with an operating rod dismount notch, a `lock comprising a cylindrical body portion and a finger .piece attached thereto, said body portion adapted to be inserted within va recess inthe receiver above said dismount notch, all adapted and arranged whereby said lock blocks the dismount notch thereby preventing the operating rod from disengagement with the receiver at thedismount notch.

6. In a firearm having a receiver, a reciprocable bolt and an operating rod connectedthereto, the receiver being provided with an operating rod dismount notch, a lock comprising a cylindrical body portion and a finger piece attached thereto, said body portion adapted to be inserted within `a recess in the receiver above said dismount notch, means to retain said body portion in said recess, and resilient means exerting a bias on saidA .body portion providing a first and second transverse lposition of said lock, all adapted and arranged whereby said lock in said first transverse position blocks said dismount notch thereby preventing the operating rod from disengagement with the receiver at 'said dismount notch and the disengagement of the operating rod from the receiver at said ldismount notch when said lock is in said second transverse position.

JOHN'C. GARAND.

REFER/ENOES CITED The following references are of .record in the file of this patent:

Number Name Date 449,352 Mauser Mar. 3l, 1891 1,842,847 Stange Jan. 26, .1932 1,843,916 Cole Feb. 9, 1932 

